1 /* Close a shared object opened by `_dl_open'.
2 Copyright (C) 1996, 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
3 This file is part of the GNU C Library.
5 The GNU C Library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Library General Public License as
7 published by the Free Software Foundation; either version 2 of the
8 License, or (at your option) any later version.
10 The GNU C Library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Library General Public License for more details.
15 You should have received a copy of the GNU Library General Public
16 License along with the GNU C Library; see the file COPYING.LIB. If not,
17 write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
18 Boston, MA 02111-1307, USA. */
25 #include <bits/libc-lock.h>
27 #include <sys/types.h>
31 /* Type of the constructor functions. */
32 typedef void (*fini_t
) (void);
35 /* During the program run we must not modify the global data of
36 loaded shared object simultanously in two threads. Therefore we
37 protect `dlopen' and `dlclose' in dlclose.c. */
38 __libc_lock_define (extern, _dl_load_lock
)
42 _dl_close (void *_map
)
44 struct link_map
**list
;
45 struct link_map
**rellist
;
46 struct link_map
*map
= _map
;
47 unsigned int nsearchlist
;
48 unsigned int nrellist
;
51 if (map
->l_opencount
== 0)
52 _dl_signal_error (0, map
->l_name
, N_("shared object not open"));
54 /* Acquire the lock. */
55 __libc_lock_lock (_dl_load_lock
);
57 /* Decrement the reference count. */
58 if (map
->l_opencount
> 1 || map
->l_type
!= lt_loaded
)
60 /* There are still references to this object. Do nothing more. */
62 __libc_lock_unlock (_dl_load_lock
);
66 list
= map
->l_searchlist
.r_list
;
67 nsearchlist
= map
->l_searchlist
.r_nlist
;
69 rellist
= map
->l_reldeps
;
70 nrellist
= map
->l_reldepsact
;
72 /* Call all termination functions at once. */
73 for (i
= 0; i
< nsearchlist
; ++i
)
75 struct link_map
*imap
= map
->l_initfini
[i
];
76 if (imap
->l_opencount
== 1 && imap
->l_type
== lt_loaded
77 && (imap
->l_info
[DT_FINI
] || imap
->l_info
[DT_FINI_ARRAY
])
78 /* Skip any half-cooked objects that were never initialized. */
79 && imap
->l_init_called
)
81 /* When debugging print a message first. */
82 if (__builtin_expect (_dl_debug_impcalls
, 0))
83 _dl_debug_message (1, "\ncalling fini: ", imap
->l_name
,
86 /* Call its termination function. */
87 if (imap
->l_info
[DT_FINI_ARRAY
] != NULL
)
90 (ElfW(Addr
) *) (imap
->l_addr
91 + imap
->l_info
[DT_FINI_ARRAY
]->d_un
.d_ptr
);
92 unsigned int sz
= (imap
->l_info
[DT_FINI_ARRAYSZ
]->d_un
.d_val
93 / sizeof (ElfW(Addr
)));
96 for (cnt
= 0; cnt
< sz
; ++cnt
)
97 ((fini_t
) (imap
->l_addr
+ array
[cnt
])) ();
100 /* Next try the old-style destructor. */
101 if (imap
->l_info
[DT_FINI
] != NULL
)
102 (*(void (*) (void)) ((void *) imap
->l_addr
103 + imap
->l_info
[DT_FINI
]->d_un
.d_ptr
)) ();
107 /* Notify the debugger we are about to remove some loaded objects. */
108 _r_debug
.r_state
= RT_DELETE
;
111 /* The search list contains a counted reference to each object it
112 points to, the 0th elt being MAP itself. Decrement the reference
113 counts on all the objects MAP depends on. */
114 for (i
= 0; i
< nsearchlist
; ++i
)
115 --list
[i
]->l_opencount
;
117 /* Check each element of the search list to see if all references to
119 for (i
= 0; i
< nsearchlist
; ++i
)
121 struct link_map
*imap
= list
[i
];
122 if (imap
->l_opencount
== 0 && imap
->l_type
== lt_loaded
)
124 struct libname_list
*lnp
;
126 /* That was the last reference, and this was a dlopen-loaded
127 object. We can unmap it. */
130 /* This object is in the global scope list. Remove it. */
131 int cnt
= _dl_main_searchlist
->r_nlist
;
135 while (_dl_main_searchlist
->r_list
[cnt
] != imap
);
137 /* The object was already correctly registered. */
138 while (++cnt
< _dl_main_searchlist
->r_nlist
)
139 _dl_main_searchlist
->r_list
[cnt
- 1]
140 = _dl_main_searchlist
->r_list
[cnt
];
142 --_dl_main_searchlist
->r_nlist
;
145 /* We can unmap all the maps at once. We determined the
146 start address and length when we loaded the object and
147 the `munmap' call does the rest. */
148 __munmap ((void *) imap
->l_map_start
,
149 imap
->l_map_end
- imap
->l_map_start
);
151 /* Finally, unlink the data structure and free it. */
153 /* We will unlink the first object only if this is a statically
155 assert (imap
->l_prev
!= NULL
);
156 imap
->l_prev
->l_next
= imap
->l_next
;
158 if (imap
->l_prev
!= NULL
)
159 imap
->l_prev
->l_next
= imap
->l_next
;
161 _dl_loaded
= imap
->l_next
;
164 imap
->l_next
->l_prev
= imap
->l_prev
;
166 if (imap
->l_versions
!= NULL
)
167 free (imap
->l_versions
);
168 if (imap
->l_origin
!= NULL
&& imap
->l_origin
!= (char *) -1)
169 free ((char *) imap
->l_origin
);
171 /* This name always is allocated. */
173 /* Remove the list with all the names of the shared object. */
174 lnp
= imap
->l_libname
;
177 struct libname_list
*this = lnp
;
183 /* Remove the searchlists. */
186 if (imap
->l_searchlist
.r_list
!= NULL
)
187 free (imap
->l_searchlist
.r_list
);
188 else if (imap
->l_initfini
!= NULL
)
189 free (imap
->l_initfini
);
192 if (imap
->l_phdr_allocated
)
193 free ((void *) imap
->l_phdr
);
199 /* Now we can perhaps also remove the modules for which we had
200 dependencies because of symbol lookup. */
203 while (nrellist
-- > 0)
204 _dl_close (rellist
[nrellist
]);
211 if (_dl_global_scope_alloc
!= 0
212 && _dl_main_searchlist
->r_nlist
== _dl_initial_searchlist
.r_nlist
)
214 /* All object dynamically loaded by the program are unloaded. Free
215 the memory allocated for the global scope variable. */
216 struct link_map
**old
= _dl_main_searchlist
->r_list
;
218 /* Put the old map in. */
219 _dl_main_searchlist
->r_list
= _dl_initial_searchlist
.r_list
;
220 /* Signal that the original map is used. */
221 _dl_global_scope_alloc
= 0;
223 /* Now free the old map. */
227 /* Notify the debugger those objects are finalized and gone. */
228 _r_debug
.r_state
= RT_CONSISTENT
;
231 /* Release the lock. */
232 __libc_lock_unlock (_dl_load_lock
);